N₂O is a typical by-product in the NH₃-SCR process, which requires urgent resolution due to its negative economic and environmental impacts. This study investigates in detail the mechanism of N₂O generation on the surface of the Mn-Ce/TiO₂ catalyst (Mn-Ce/TiO₂-ZS) with anatase {001} facets preferentially exposed. The deep oxidation of NH₃ and *NH₂ capture of NO via O₂ were proved to be the dominant N₂O generation pathways. The production of N₂O was remarkably reduced by the introduction of a low percentage of water vapor (H₂O). The results revealed that low percentage of H₂O was capable of enhancing the acid sites on the catalyst surface and facilitating the generation of active hydroxyl species. These active species inhibited the deep dehydrogenation of ammonia and the disintegration of nitrate species on the catalyst surface, as well as suppressing the generation of N₂O.

中文翻译：

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水蒸气抑制NH3-SCR过程中N2O生成的机制


N₂O 是 NH ₃ -SCR 工艺中的典型副产品，由于其对经济和环境的负面影响，需要紧急解决。本研究详细研究了锐钛矿{001}面优先暴露的 Mn-Ce/TiO ₂ 催化剂 （Mn-Ce/TiO ₂ -ZS） 表面产生 N ₂ O 的机制。NH 的深度氧化 ₃ 和 *NH 通过 O _{2 2} 捕获 NO 被证明是主要的 N ₂ O 生成途径。通过引入低百分比的水蒸气 （H ₂ O） ，N ₂ O 的产生显着减少。结果表明，低百分比的 H ₂ O 能够增强催化剂表面的酸位点并促进活性羟基物种的产生。这些活性物质抑制了氨的深度脱氢和催化剂表面硝酸盐物质的分解，并抑制了 N ₂ O 的产生。